Solderless electrical connector



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soLDERLEss ELECTRICAL CONNECTOR FiledvAug. 5, 1955 May 19, 19592,887,667

ATTORNEY y I INVENToRj 44 45 ,47 9 5 .5l Fl". 7 fo@ 42 45 5545/ (i1/2 9Unid. States Patte* xT 2,887,667 y f soLDERLEss ELECTRICAL CoNNacTon fiWilliam E.Wolfe, Philadelphia, and Robert A. Iulorn, i i Doylestown, Pa.j

Application August 5, 1955, Serial No,` 526,601

Our invention relates to electrical conductor terminals,

and more particularly relates to solderless type terminals for shieldedand coaxial cables. i t j t The shielded and coaxial cables used asinterconnections between electronic devices is usually comprised of avery line stranded or tinsel center lead surrounded by a tubularinsulation. tral lead, and over the tubular insulatiomisfastranded wirelead which is used as a companion lead for the cen-l ter lead and ashielding means fory the center lead. Surrounding the coaxial leadandover the entire assembly is a'sheath of insulating material. As it isvery diilicult toy make a satisfactory electrical connection to the linecenter lead of the cable, it is an object offour invention to devise asolderless,` terminal for a coaxial cable that is readily and securelyapplied to the coaxial cable end.

Another object of ourinvention is to devise a terminal for a coaxialcable that provides positive electrical connection tbetween the currentcarrying parts of. the terminal and the current carrying leads of thecable.

Another object of our `invention is to devise an electrical terminal fora coaxial cable that provides definite securing of the coaxial lead toprevent movement be` tween the current carrying parts of the terminaland the attached leads and thus prevent destruction of the electricalconnection.

, Another object of our invention isto devise an electrical terminalfora coaxial cable having the current carrying elements of the terminalcoaxially disposed.

Other objects of our invention are to provide an improved device of thecharacter described, which is easily and economically produced, which issturdy and compact in construction, and which provides positive andsecure termination for the leads of a coaxialror shielded cable. Withtheabove and related objects inview, our invention consists in thedetails of construction as hereinafter shall be set forth, and thedescription will be more readily understoodwhen read in conjunction withthe accompanyinezdrawingsiinwhich: 1 y s f f `Fig.l lisfan isometricviewof a preferred embodiment of our improved terminal showing theterminal applied to the leads of a coaxial cable.

Fig. 2 is an isometric view of the female portion of our improvedconnector shown positioned in the panel of an electronic device chassis.

Fig. 3 is a sectional elevational view taken along the line 3--3 of Fig.1.

Fig. 4 is an isometric view showing a modified method of securing thecoaxial cable to the terminal and making electrical contact to theshielding lead of the cable (cable not shown).

Fig. 5 is an isometric view of the modified method of cable securingshowing the securing means formed over the shielding lead of the cable.

Fig. 6 is an isometric view of a modified form of our improved coaxialcable terminal.

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t* limited'- llexing of the contacting shield so that it can` beCoaxially disposedaround `the cen- J i,

pressed onto and have a positive electrical contactwith the'shield ofthe receptacle portion R, hereinafter described. A shoulderedcylindrical portion 12 of the contacting shield 10 is arranged tointerfit with a hole 13 W in a handle member 14, the cylindrical portion12 being expandedv at 12A to fixedly secure the contacting shield indefinite space relationship to the handle, generally designated las H.The contact making element 15 of the plugunit Pis cylindrical in shapewith a closed semi-spherical end 16. The inner end 17 of the contactmakingelement 15 is arranged `to intert with a hole 18 ina disc-shapedinsulating spacer member 19. The spacer member 19 is positioned by ashouldered portion 20 of the contacting shield 10 and is secured inplace by a portion of the metal that is cut out of the slots 11 in thecontacting shield. The metal cut out of the slots is allowed to lremainattached to the contacting shield `10 at. the;,`bottom of the slots. Aportion of the strip of metal is then cut olf and the balance 11A isbent inward to secure the disc-shaped insulating member 19 (see Fig. 3).A portion ofthe cylindrical wall of the contactmaking element 15 isexpanded to form a shoulder 21 which interlits with one side of thedisc-shaped insulating .spacer member 19. The inner end 22 of thecontact making element 15 is expanded against the inner sideof `the`disc-shaped insulating member 19 to denitely position the contactmaking element in coaxial space relationship with the contact `makingshield 10. Force litting Within the bore '23 of the contact makingelement 15 is a cylindrical metal insert 24 having a pointed shaft Zionits inner end (see Fig. 3).

When a mechanic wishes to applythe plug unit P to a shielded or coaxialcable, generally designatedas L,

he lirst `strips about one inch of the sheath 30 from the cable Lexposing the stranded shielding coaxial lead 31,

then cuts 01T about one-half inch of the stranded shield coaxial lead31, exposing the tubular insulation 32 over the central lead 33. Themechanic then forces the tubular insulation 32 together with the centrallead 33 onto the pointedshaft` 25, so that the pointed shaft 25 entersthebore* of the tubular insulation 32 and makes positive contact `,with`the central lead 33.

14-ibyway-of'the securing screw 35 to provide mechanical securing of theshielded or coaxial cable to the plug unit and electrical connection ofthe stranded shielding coaxial lead 31 to the plug unit P.

In Figs. 4 and 5 is illustrated a modified form of securing for thestranded shielded coaxial cable lead L. In this embodiment, upwardlyextending fingers 34A cut and formed from the metal of the handle unitH1 (see Fig. 4), are spaced and positioned so that they can be bentaround the stranded coaxial lead of the cable L (see Fig. 5), to providemechanical securing of the shielded or coaxial cable to the plug unitand electrical connection of the stranded shielding coaxial lead 3i) tothe plug unit P1.

The receptacle or female unit R (see Fig. 2), is comprised of acylindrical shielding element 36 within which is iixedly positioned adisc-shaped insulating member 37 having a central hole 38 in which isxedly positioned a.

n i A relief or securing .clampI 341s then `fixedly attached to thehandle member tact 'element 39 is arranged to receive and make contact'-with the contact making element 15 of the plug unit P. Wire connections(not shown) to electronic devices -(not shown) within the chassis aresoldered Vto 'theY inner end of the female contact element 39. Thecylindrical shield element 36 is iixedly mounted on the Vmetal panel--41lof the chassis, generally designatedC. 'v j f From the abovedescription and the illustrations, itwilll be readily observed thatsecure and positive connection can be made to a shielded or coaxialcable with little effort on the part of the mechanic making theapplication. In Figs. 6 and 7 is illustrated a modiiied embodiment 'ofour improved connector. In -this embodimentfthe coaxial relationship ofthe conducting parts is maintained throughout the plug unit P1 andreceptacle unit R. In' the latter embodiment, the contacting shield 10A,`slots 11B, shouldered cylindrical portion l22A, contact making element15A, disc-shaped insulating spacer member 19A, and cylindrical metalinsert 24A, with pointed shaft 25A are arranged in the same manner ascorresponding parts of the first described embodiment. However, inthelatter embodiment, the contacting shield 10A is lixedly secured l 4shielded or coaxial cable L, he rst strips about one and one-half inchesof sheath 30 from the cable'L, Aexposing by crimping to a cylindricaltapered body member-43 *A hole 44, extending longitudinally through thecenterof 1the cylindrical tapered body member, yprovides definite eo{axial space relationship between the pointed shaft 25A, which extendslongitudinally through the hole `44, and the metallic wall of thecylindrical tapered body member 43.

A reduced diameter hole 4S, adjacent to the tapered end 46 of thecylindrical tapered body member 43, is of a size that neatly intertswith the external vsurface of the tubular insulation 32 of the shieldedor coaxial cable. With 'this' arrangement, it can readily be observedthat when th'e 'v" lead 33. The tapered end 46 of the cylindricaltapered i' body member 43 is arranged to intert with an-internal taper47 in the handle member H1. When the plugl unit P1 is assembled, thestranded shielding coaxial lead 310i cable L is arranged to bepositioned between the tapered end 46 of the body portion 43 and theinternal taper 47 in the handle H1 (see Fig. 7). lnterttinghelical'threads on the body portion 43 and handle unit H1 at 48 providefor definite securing of the body portion 43 and handle H1 and clampingaction between the tapered end 46 of the tapered body portion 43 and theinternal taper 47 in the handle unit H2 to provide denite electricalconnection for the coaxial lead 31 and mechanical securing for 'thecable L. A constriction 49 in the lateral hole in thehandle unit H2 isof a size that neatly interlits withthe external surface of the coaxiallead 31 and a hole '50, tapered at its inner end 51 and of a size toneatly interit with the sheath of the cable L, is provided in the'handle unit H2. The handle portion H2 of the plug P1 may be fabricatedfrom metal or insulating material.

When a mechanic wishes to apply the plug unit P1 11o-al the strandedshielding coaxial lead 31. He then threads the cable end into the handleunit. The taper 51 in the hole assists the mechanic in this operationuntil the cut sheath end 52 abuts the tapered end 51 of the hole 50.With the cable in this latter position, the cut end of the cable extendsabout one-half inch beyond the threadedend of the handle unit H2. Themechanic now flares the stranded coaxial lead 31 slightly, and threadsthe tubular insulation 32 into the hole 44 on the threaded body member43, the-central lead 33 making contact with the pointed shaft 25A, andthen forms'the strands vof the stranded coaxial lead over the taper 46of the body portion 43. He now slides the handle unit H2 up and engagesthe interiitting helical threads 48 on the body portion 43 and handleunit H2 to secure the entire assembly and electrically connect thecentral lead 33 and coaxial leadl to the plug unit P1.

From the above description and illustrations of the latter embodiment,it can readily be observed that coaxial positioning vof the currentcarrying parts and leads is maintained throughout the entire plugassembly P1. The strandedfshielding coaxial lead 31, being Iincoaxiallyl spaced relationship to the central lead 33; the cylindricaltapered -body member 43,"being in coaxially spaced relationship with thepointed shaft 25A; and the contacting shield 10A being in coaxiallyspaced relationship to the contact making element 15A.

v#lh'e receptacle unit employed with the plug unit P1 is the same asthat used with the plug unit P and as illus tratedl in Fig. 2 anddescribed above.

`Although our invention has been described in considerable detail, suchdescription is intended asbeing illus-V trative rather than as limiting,as the invention may be variously embodied, and the scope of theinvention is -to be determined as claimed.

We claimy as our invention:

A coaxial and shielding cable terminal 'comprising a tubular contactingshield, a disc shaped insulating membe'r held within said tubularcontacting shield, a pointed shaft `held by a metallic insert andcentrally supported upon said insulated'disc, a handle member secured tothe outside of said -contacting shield, a relief clamp detach-` ablysecured to said handle and being adapted to grasp the insulation of acable, said pointed shaft'being adapted to :pierce one end of the cablewhereby electrical contact is made by the metal insert.

References Cited in the tile of this patent

